Fix TypedArray.slice with external array buffer (#3080)

In case of TypedArrays which were constructed with an ArrayBuffer
the `slice` method incorrectly added the `byteOffset` value of
when the elements were copied.

There is no need to add the `byteOffset` value for the ArrayBuffer's
contents pointer as it is already added by the `ecma_typedarray_get_buffer`
call.

JerryScript-DCO-1.0-Signed-off-by: Peter Gal pgal.u-szeged@partner.samsung.com

jerry-core/ecma/builtin-objects/typedarray/ecma-builtin-typedarray-prototype.c

@@ -1967,8 +1967,7 @@ ecma_builtin_typedarray_prototype_slice (ecma_value_t this_arg, /**< this argume
 
     ecma_object_t *new_typedarray_p = ecma_get_object_from_value (new_typedarray);
     lit_utf8_byte_t *new_typedarray_buffer_p = ecma_typedarray_get_buffer (new_typedarray_p);
-    ecma_length_t src_byte_offset = ecma_typedarray_get_offset (typedarray_p);
-    uint32_t src_byte_index = (start * element_size) + src_byte_offset;
+    uint32_t src_byte_index = (start * element_size);
 
     memcpy (new_typedarray_buffer_p,
             typedarray_buffer_p + src_byte_index,

tests/jerry/es2015/regression-test-issue-3078.js

@@ -0,0 +1,21 @@
+// Copyright JS Foundation and other contributors, http://js.foundation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+var arrb = new ArrayBuffer(13);
+var arr = new Uint8Array(arrb, 9);
+for (var idx = 0; idx < arr.length; idx++) {
+  arr[idx] = idx + 1;
+}
+
+assert(arr.slice(1).toString() == "2,3,4");

tests/jerry/es2015/typedarray-prototype-slice-ext-arraybuffer.js

@@ -0,0 +1,71 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+var typedarrays = [
+  Uint8ClampedArray,
+  Uint8Array,
+  Uint16Array,
+  Uint32Array,
+  Float32Array,
+  Float64Array,
+  Int8Array,
+  Int16Array,
+  Int32Array,
+];
+
+for (var typeIdx = 0; typeIdx < typedarrays.length; typeIdx++) {
+  var buffer = new ArrayBuffer(100);
+  var typed = new typedarrays[typeIdx](buffer, 8, 6);
+  try {
+    typed.prototype.slice.call(undefined);
+    assert(false);
+  } catch (err) {
+    assert(err instanceof TypeError);
+  }
+
+  for (var idx = 0; idx < typed.length; idx++) {
+    typed[idx] = idx;
+  }
+
+  // Test with normal inputs
+  assert(typed.slice(1, 3).toString() === "1,2");
+  assert(typed.slice(2, 5).toString() === "2,3,4");
+  assert(typed.slice(0, 6).toString() === "0,1,2,3,4,5");
+
+  // Test witn negative inputs
+  assert(typed.slice(-2, 5).toString() === "4");
+  assert(typed.slice(0, -3).toString() === "0,1,2");
+  assert(typed.slice(-1, -4).toString() === "");
+
+  // Test with bigger inputs then length
+  assert(typed.slice(7, 1).toString() === "");
+  assert(typed.slice(2, 9).toString() === "2,3,4,5");
+
+  // Test with undefined
+  assert(typed.slice(undefined, 4).toString() === "0,1,2,3");
+  assert(typed.slice(0, undefined).toString() === "0,1,2,3,4,5");
+  assert(typed.slice(undefined, undefined).toString() === "0,1,2,3,4,5");
+
+  // Test with NaN and +/-Infinity
+  assert(typed.slice(NaN, 3).toString() === "0,1,2");
+  assert(typed.slice(2, Infinity).toString() === "2,3,4,5");
+  assert(typed.slice(-Infinity, Infinity).toString() === "0,1,2,3,4,5");
+
+  // Test with default inputs
+  assert(typed.slice().toString() === "0,1,2,3,4,5");
+  assert(typed.slice(4).toString() === "4,5");
+
+  delete buffer;
+}